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Thursday, November 30, 2017

If science is what scientists do, what happens if scientists stop doing science?

“Is this still science?” has become a recurring question in the foundations of physics. Whether it’s the multiverse, string theory, supersymmetry, or inflation, concerns abound that theoreticians have crossed a line.

On the one hand, I understand the concerns about breaking with centuries of tradition. We used to followed up each hypothesis with experimental test, and the longer the delay between hypothesis and test, the easier for pseudoscience to take foothold. On the other hand, I agree that speculation is a necessary part of science and new problems sometimes require new methods. Insisting on ideals of the past might mean getting stuck, maybe forever.

Even more important, I think it’s a grave mistake to let anyone define what we mean by doing science. Because who gets to decide what’s the right thing to do? Should we listen to Helge Kragh? Peter Woit? George Ellis? Or to the other side, to people like Max Tegmark, Sean Carroll, and David Gross, who claim we’re just witnessing a little paradigm change, nothing to worry about? Or should we, heaven forbid, listen to some philosophers and their ideas about post-empirical science?

There have been many previous attempts to define what science is, but the only definition that ever made sense to me is that science is what scientists do, and scientists are people who search for useful descriptions of nature. “Science,” then, is an emergent concept that arises in communities of people with a shared work practices. “Communities of practice,” as the sociologists say.

This brings me to my problem. If science is what scientists do, then how can anything that scientists do not be science? For a long time it seemed to me that in the end we won’t get around settling on a definition for science and holding on to it, regardless of how much I’d prefer a self-organized solution.

If some scientists insist on changing the old-fashioned methodology, the communities will fall apart. Let us call the two sectors “conservatives” and “progressives.” Each of them will insist they are the ones pursuing the more promising approach.

Based on this little theory, let me make a prediction what will happen next: The split will become more formally entrenched. Members of the community will begin taking sides, if they haven’t already, and will make an effort to state their research philosophy upfront.

In the end, only time will tell which lineage will survive and which one will share the fate of the Neanderthals.

So, if science is what scientists do, what happens if some scientists stop doing science? You see it happening as we speak.

100 comments:

I guess phlogiston and aether died because something better came along?If something better comes along, the predicted split side of scientists in which it originates will survive.If nothing better comes along, it will be political clout and such that will determine who, if anyone, survives.

"In the end, only time will tell which lineage will survive and which one will share the fate of the Neanderthals.". ultimately, the fate of the 'conservative' and 'progressive' groups will be determined by $. if governments and wealthy patrons stop funding theoretical research that is divorced from experiment, research organizations and universities will stop hiring people to do that kind of research. and the decision to fund or not fund certain kinds of research is inevitably based on politically determined considerations involving fiscal matters. e.g. tax policy, like it or not in this world, 'money talks'.

Noone claims that string theory or M theory or supersymmetry are scientific theories. They are mathematical models that are consistent with all experimentally verified models and make claims that have yet to be experimentally verified. They claim that they could be scientific theories.

And no-one complains that mathematicians explore all kinds of mathematics just because they find the interesting. So why should not theoretical physicists? In fact they are mathematics focused on mathematical models that have been experimentally verified and could be experimentally verified.

Of course, it might be that some claims cannot be experimentally verified because we simply will never have the technology or access to extreme conditions. Then they stay mathematical theories.

Whether string theory or M theory are the right approaches, noone knows and you can well argue that most departments are putting their money on the wrong horse.

In Steven Weinberg's book Dreams of a Final Theory, he thoughtfully concludes that one can talk about the art of science, but that there is no use trying to codify a "science" of science. He also devotes a chapter to lambasting the philosophy of science. He allows that science philosophers are useful only to the extent that they protect scientists from other philosophers. That sounds pretty cantankerous but it's very well argued.

I wish I had my copy of this book on hand, as it's very quotable. He covers three historical examples of the healthy interaction between theory and experiment. Any rules one might conclude from one example is going to be violated by another one.

There IS a solution to the problem, and it is called DEDUCTION. Clearly formulated initial assumptions (axioms; postulates) plus explicit arguments that can be checked for validity. You say almost the same here:

Sabine Hossenfelder: "But today in the foundations of physics, theory-development proceeds largely without experimental feedback. In such cases, keeping track of assumptions is crucial - otherwise it becomes impossible to tell what really follows from what. Or, I should say, it would be crucial because theoretical physicists are bad at this. The result is that some research areas can amass loosely connected arguments that follow from a set of assumptions that aren't written down anywhere. This might result in an entirely self-consistent construction and yet not have anything to do with reality. If the underlying assumptions aren't written down anywhere, the result is conceptual mud in which case we can't tell philosophy from mathematics. [...] Every theory needs assumptions. The problem isn't the existence of assumptions, the problem is the lack of clarity about what exactly is assumed and what follows from what." http://backreaction.blogspot.bg/2016/12/no-physicists-have-no-fear-of-math-but.html

I don't think "science is what scientists do" is an acceptable definition of science. If science is what scientists do, what is it when scientists do fraudulent science, e.g., all the recent retractions of papers? Scientific fraud isn't science, but it's something some scientists do. If you try to get around this by saying those weren't scientists committing fraud, then you're turning it into a circular definition: science is what scientists do and those who do science are scientists. The community of scientists need to define science not just by what they do, but also by what they accept as valid science. But how can they continue to do that during times like these without some agreed upon definition of science?

Reminder; it was controversial to even have professionals named "scientists" before that there was just natural philosophy. At least in Europe.

It doesn't matter what scientists or non-scientists call the search for truth- what matters is whether its true or not. You obviously can't say that any non-empirical approach won't work, but at some point theories you make up will have to be tested in which case you will find out you are right, wrong, partially right or maybe the entire framework you had of the earth being a big dome is wrong and some of your assumptions need to change.

At this point, I doubt too many astounding advances will come out of American Universities except maybe in physics since they seem to think that everything is so offensive to talk about. I'll say that. Eventually it'll work it's way to the physics department too though.

Three thoughts:1. One of Kuhn's claims about why science makes progress was that the scientists in a particular field are pretty homogeneous in terms training and expectations, and can generally agree on what looks like progress and failure. That would no longer be the case in the situation you describe, so those fields of physics would look more like the humanities.2. I think the science / not science discussion (interesting though it is) is actually of lesser importance. Where these theories are increasingly in trouble, it seems to me, is basic motivation. Back when string theory and inflation were getting started, they appealed to the concerns of the day; but the GUTs that made people worry about monopoles are no longer so promising, the supersymmetry that would solve the hierarchy problem has been pushed to an irrelevant energy scale. Rather than being in the position of promoting new ideas on their merits, practitioners are now in the business of defending old ideas as still relevant. That's a psychologically very different space. 3. Nothing wrong with speculation -- it's fun and healthy. But a crucial part of what makes science *science* is what happens next. A thought is not a theory.

Mind Blown. If science is what scientists do, and scientist aren't doing it, then can anyone not do it? i.e. not need to be scientist to do it, either way. (Is this a thesis?) I think not. In fact, isn't the provability or rather the disprovable nature of science a key to the dilemma? Isn't the point that the two perspectives diverge from this nature?Related tangent or un-thesis: Has physics departed from the sciences in it's over-dependence on math? Or is it math's departure from reality? Or the inability to define the reality of it's variables? Of which I now have too many. Or should I have said the inability to define the variables of it's reality?

Science is an empirically relevant spare operating system embracing undesired observations. Science is a nudist colony with math.

Physical theory and economics offer big thoughts and starving nations. Saepe errans, numquam dubitans. Non-classical gravitation, composition of the universe, and SUSY are 50 years and a million+ published pages of empirical failure.

Do opposite shoes (DOI:10.1107/S0108767303004161, Section 3ff) violate the Equivalence Principle? A better idea need only be testable. It is believable afterward. Untestable promises buying more decimal places of anticipation is religion.

You write: "Noone claims that string theory or M theory or supersymmetry are scientific theories."

This is clearly wrong. Go and ask anyone who works on these topics whether these are scientific theories, and I estimate that you will get the answer "yes" in 99+-1% of the time. As naive theorist says above, this is a funding issue. If they'd admit it's not science, they'd cut off their income.

Communities have guidelines and work ethics. That's why we have a definition of scientific misconduct and fraud and guidelines for good peer review (and titles to begin with). My point being, these are not hard-coded, they are formulated by the community and they are updated over time.

I like the idea of speculative science; maybe science is so large a beast that there are scientists simply chasing the speculative ideas; and others, more conservative, digging around the science that has been tried, tested and found trust-worthy.

If scientists stop doing science, then maybe citizens start doing science - aka citizen science, but there are some obvious and non-obvious problems with that too: https://aeon.co/essays/is-grassroots-citizen-science-a-front-for-big-business

On a separate note is there a way of inserting a link without the whole of the link being visible?

Didn't some smart guy say "science procedes one funeral at a time"? Science always deals in the realm of the metaphysical. Our theory of the world will always exist in our minds.

Progress has stalled for a minute thanks to the overwhelming mathematical promise of some incorrect theories from 40 years ago. We'll need some wild speculation and a few deaths to dig ourselves out of this trap. But never fear: for 400 years the scientific field has always found a way.

"Deductions only work for mathematical proofs, but physics isn't math"

Below Einstein defines two types of theory - empirical and deductive:

Albert Einstein: "From a systematic theoretical point of view, we may imagine the process of evolution of an empirical science to be a continuous process of induction. Theories are evolved and are expressed in short compass as statements of a large number of individual observations in the form of empirical laws, from which the general laws can be ascertained by comparison. Regarded in this way, the development of a science bears some resemblance to the compilation of a classified catalogue. It is, as it were, a purely empirical enterprise. But this point of view by no means embraces the whole of the actual process ; for it slurs over the important part played by intuition and deductive thought in the development of an exact science. As soon as a science has emerged from its initial stages, theoretical advances are no longer achieved merely by a process of arrangement. Guided by empirical data, the investigator rather develops a system of thought which, in general, is built up logically from a small number of fundamental assumptions, the so-called axioms." https://www.marxists.org/reference/archive/einstein/works/1910s/relative/ap03.htm

In other words, equations in a physics theory are either GUESSED, or (possibly guessed initially but then rigorously) DEDUCED from "a small number of fundamental assumptions, the so-called axioms":

Richard Feynman: "Dirac discovered the correct laws for relativity quantum mechanics simply by guessing the equation. The method of guessing the equation seems to be a pretty effective way of guessing new laws." http://dillydust.com/The%20Character%20of%20Physical%20Law~tqw~_darksiderg.pdf

In my view, if the "fundamental assumptions, the so-called axioms" are missing or not clearly defined, and if the logical paths leading from them to the conclusions of the theory are not explicit, the theory is not even wrong.

I don't share your optimism. Modern life doesn't work without scientific knowledge. We have created too many problems for whose solutions we need science. We better make sure that science works well and we don't have 400 years time to wait. You can shrug off the problems in the foundations of physics because they don't have all that much relevance for daily life. But if you can't trust physicists, how do you know you can trust any other scientists?

Tom Weidig said..."I just don't understand what all the fuzz is about.". you should read lee smolin's book.part of the fuss is that the limited number of tenured or tenure-track university faculty positions are being taken by pseudo-scientists (mathematicians posing as theoretical physicists), resulting in the shutting out of individuals who could be doing and teaching real physics. That may benefit Wall Street (the primary second-choice employer of theoretical physicists who can't get academic positions) but not the physics community or society as a whole (it is not clear that quants have improved the quality of life of the average non-investors).

John Baez said "It's just like how whenever anyone tries to play music, no matter how awful it sounds, it's still music. It's just bad music.". there's a fundamental difference between bad music and cacaphony.

"Mathematical consistency is a necessary criterion, but not a sufficient one. You can deduce from your axioms all you want, but you can never deduce the axioms."

Yes. In mathematics, that seems to be the end of the story. In physics, one can falsify the axioms or their consequences empirically. Note, however, that only deductive (consistent) theories can be falsified. The deductive structure allows one to interpret the detected falsehood in terms of the whole theory. In the absence of a deductive structure any detected falsehood remains marginal and insignificant - one can safely ignore it or "fix" it in some way, e.g. by introducing a fudge factor.

What happens when a 'soft' science such as sociology is elevated to the level of physics because we find that social behavior works at many levels - say well beyond human or animal? By elevated I mean its predictions provide useful data that describes key aspects of nature just like any science. Although we are not there yet, this would then expand population yet dilute the purview of a scientists. What would they do? Extend theoretical knowledge. Science? If its furnished with metrics - yes. Now what happens if humans extend in such a way that different sets have different sets of senses? Do multiple sciences emerge?

But they might be to proud, to old, to stubborn for that. And they might be living in a social bubble which convinces them they are on the right track.

* Focus on restructuring physics education.

Attract students of a more diverse aptitude (read: not just mathematical aptitude). Because diversity is the mother of intelligent problem solving. Complementary skills working together.So not replacing, but installing a parallel trajectory in physics education, with generalists, creatives,..Then teach those 2 groups how to respect each other, e.g. by doing projects together, so in later careers they will understand the value of that synergy.

But this will meet with opposition, because those in charge, those with influence, are primarily mathematically oriented, and thus stand to gain nothing. Unless of course they have enough vision to strive for community gain.

I don't know if anyone has ever been able to find a good definition of 'soft' vs 'hard' science, but the obvious answer to your question what happens with a soft science if it begins fitting and predicting data to good accuracy is that it's no longer all that soft.

I suspect that the current dominance of the "progressives", with their untestable ideas is not a permanent state of affairs, and that the pendulum will swing slowly, but inexorably, towards the "conservative" mindset, unless some startling new experimental evidence breathes life back into one of the "progressive" models. Even if the experimental parameter space of the "progressive" models shrinks to zero, in the coming years, a remnant of the progressive ideology will, no doubt, persist just as a residual of Neanderthal DNA is retained in modern European-derived people.

Classical atomism was based on completely intertwined wholes.Modernity seeks salvation in the knowledge of the "part in itself".The atomists saw that indestructible wholeness that does not require a process of creation, that whole which must be contained in all. They would have been happy to prove that all-inclusive All with all, which is called gravitation.Whereas the singularity seekers still bite their teeth on this all-embracing.The atomists believe in the formula: "One contains all, but all contain one.Whereas modernity now has to construct thousands of Babylonian linguistic towers to create bridges between their isolated "particles," gravitationally, these "unbelievers" fail to trust nature, but then pitifully.So there is still that statement by Max Planck: In our lifetime, we find out nothing about nature, because we risk too little speculation and too much stuck to the outdated.

Lots of people are doing No True Scotsman. I think it's important to not do this, but I can see why it is attractive. People would like science to be "special," a somehow more noble pursuit than music or carpentry, they'd like a little capital T Truth, but I think settling for Useful isn't really so bad.

I think the issue is when people get attached to their theories, and also when physicists who are really doing math want to avoid the math departments. I've taken math courses in grad school, they're really perfectly pleasant and the people can be quite nice! If the string theorists would go hang out with the algebraic geometers they might even do something Useful. I think the only thing keeping people from doing that is either a fear of being subjected to mathematical rigors, or perhaps some chauvinism that if their results are "Just Math" then they must not be all that interesting or useful.

My own grad work was in mathematical physics, which is a weird little field. hep-th and gr-qc can get a little wild, math-ph behaves a little better. Or just more honestly, which I'll take. I think these kinds of research using pure mathematical tools are rewarding when you are anchored in something you really believe. Taking AdS/CFT as an axiom and running with it is a very different beast than working on things like algebraic quantum field theory. Or at least, so says my community of practice.

“Citizen science” Personal fulfillment as contributor not originator is OK. Citizen science is about involvement not money. How many Rothschilds were obsessed with fleas? Just Miriam, but...wow! Abandoning a quest for something more preferred is also OK.

People watch sports. Voluntarily invest in civilization. Mass scanning of noise for signals is no sin. Social intent-imposed horrors of American education are sin incarnate.

The black fear is empowering the so tiny fraction of superior minds who attack comfortable formalized ignorance – and make it stick. Pooches are cherished, putsches are not.

This is an important discussion. Not all cosmologists are upfront in spelling out the philosophical/epistomological metaphysics behind their physics. For instance, much of the impetus (if not the main reason), for theories like inflation and the multiverse, is the pursuit by Naturalists to find alternatives to what would otherwise look too much like Intelligent Design - which, as Naturalists, they are by definition unalterably opposed to even considering.

Aristotle was a very intelligent person who came up with a lot of speculative hypotheses which turned out to be wrong (and some correct ones) and therefore seem slightly ridiculous today. If he had more and better data he would have done better. It took some time to develop the tools, such as telescopes and microscopes and statistical analysis, to get the better data.

My guess is that the issue discussed in this post is mainly due to the same problem Aristotle had - lack of better data; that we have almost exhausted the insights to be gained from what our telescopes and other tools can discover, and new and better tools are very expensive.

We will get a blip in data acquisition from LIGO (which took years to develop and build) and maybe other big developments every few decades, but the era when lots of new data was easily available seems to be over. (I will be happy to be proved wrong.)

Exponential growth in anything can not go on forever. Science had such growth over the past several centuries.

Dr. Hossenfelder's notion of 'science' seems to have observational merit. But ... is this true over all fields of scientific inquiry, and if not what distinguishes the have-nots from the haves? To the best of my (extremely limited) knowledge, chemistry doesn't seem to have 'progressive' and 'conservative' tracks. Nor does molecular biology. If I had to speculate, I'd guess that it's the amount of experimental data and the cost of acquiring it that are the sticking points. Note that this applies in spades the softer disciplines - where the experiments are easy to run but the cost of accumulating enough data to obtain statistically meaningful results can be prohibitive.

You get quantum computers! The debate about decoherence and noise started by Bill Unruh and Gil Kalai is a red herring. The Born rule is metaphysical fluff and QM just gives expectations of observables. That's it! The idea that uncertainty simply leads to computational speedups is absurd but the non-Bayesian view of probability prevails. Of course, there are no "negative probabilities" and the need for probability in QM is no different than the need for probability in any other branch of science that deals with uncertainty. The wave function can be positive, negative, spinor, complex, vector, etc... and can be used to CALCULATE probabilities that are NEVER negative. QC people believe in the Schrödinger's cat fallacy but one can interpret superposition as the observer's lack of knowledge rather than multiple worlds or other such nonsense. (Note: the uncertainty principle builds the entire foundation for QM and those who think imaginary numbers or anticommutivity are confusing should consult David Hestenes). People that talk about the interference of "probability amplitudes" are just muddying the language because amplitudes are not probabilities and probabilities do not interfere. Whenever someone starts talking Wigner, I reach for my gun.

Paul Davies pointed out that a 400-qubit computer would even come into conflict with the cosmological information bound implied by the holographic principle. It’s not only that Turing-complexity arguments cannot simply be run backwards but that there is a major debate about the completeness of mathematical descriptions in quantum mechanics. The real point is that some argue QC people are just rediscovering analog computing. I'm surprised you haven't criticized the perpetual motion machine of the 21st century.

I'm sure you're busy with things, but I would honestly recommend taking a look at David Wootton's "The Invention of Science" from 2015. He argues (very convincingly I might add, and with what seems like endless references and footnotes and detail) that science began in 1572 with the discovery of a nova by Tycho Brahe. There's obviously much more to it than that, but Wootton discusses why it was this observation (which annihilated the Ptolemaic worldview of the unchanging Heavens), coupled with an empirically oriented mindset that was beginning to take hold and the means of communication between various onlookers and educational institutions, that made astronomy the first modern science. I really do think you'd get a lot out of it. Reviews have been stellar, David clearly does his homework, and it helps to allay fears that just because we don't have a completely formal set of steps to the "scientific method," it's the general methodology of inquiry and empiricism, coupled with many individuals sharing results and conjecture, and I would likely add the rigor of mathematics (there is much about how the mathematization of the sciences, particularly physics, align tightly with the timeline of incredible growth in knowledge and technology from the Scientific Revolution up through the present day) that all allow for what we would broadly call "Science" today.

As to what comes next, I am much in line with your own thoughts. I can see where both sides are coming from, and I am very interested to see where things go in a field like fundamental physics, where we are approaching energy realms that are going to mean we either need to undertake massive efforts to construct new machines or risk progress grinding to a halt. I do like the third way out that you've mentioned before though. We should be pumping money into theoretical design for low-energy/low-cost experiments that could still somehow probe phenomena at much higher energy scales. That seems like the happy medium going forward, but more work needs to be done.

I'm with Tom Weidig on this. They are doing mathematics. The constraint on that mathematics is that it has to be consistent with the existing mathematical theory and predict or explain the same results. The goal is to find such a mathematical theory that also predicts or explains some new result that can be tested by setting up an experiment or performing and analyzing observations.

The problem is that the existing mathematics works extremely well in the areas we have been able to test it and in explaining what we have managed to observe. Unfortunately, most of these new theories are sterile. They may predict or explain something that our current theory fails to, but verifying this usually requires experiments or observations that are impossible with our existing technologies. When the tests are possible, these new theories tend to fail.

Maybe physics would be in better shape if our previous generations of physicists hadn't done such a good job.

" But if you can't trust physicists, how do you know you can trust any other scientists?"

Because they have lots of real data, and theory clearly explains it.

Or ....

Also, there is plenty of engineering that gets called science and nobody care about the distinction. And example is organic chemistry, especially synthesis. A lot of synthesis is actually magic, with only the broadest connection to theory. But lots of organic magicians are induced by theories, and usually these days are driven by (real) theories of what kind of molecule will block a certain enzyme to cure a certain disease. That's certainly a scientific approach.

This is a bit silly. Science is not what scientists "do" because some scientists do things like forge data and no one would call this "science", in fact we would regard it as "anti-science" Historically we would say that science is a methodological approach that I first learned in grade school. It involves formulating a hypothesis and then generating evidence to objectively test the hypothesis. Classically this can be in the form of experiment, but in some fields the best we can do is observation. In many areas, say medicine or biology it is a mix of both approaches. This approach has a historical track record in understanding how the physical world works as evidenced by our increasing ability to control it. ( My organic chemistry teacher once lectured that we want to understand nature so that we can make it do cool and interesting things.) This is not entirely true, but given the benefits of technology on our day to day life, from antibiotics to cell phones it is largely true. In fact it explains the public support for science in general. Theoretical physicists ( and I am an interested lay person here, no where near a practitioner) seem to be mostly in the hypothesis generation business. That is fine. So speculation is great. The issue is once you generate a hypothesis that is in principle not testable, even indirectly, than what you are doing is not science as historically understood. At least not since the time of Francis Bacon. It is closer to what Aristotle was doing. It might be related to science but as if its not testable in the way I describe above it is not likely to be as useful in figuring out how nature works. The track record of approaching the study of nature using the generation of interesting theoretical ideas that are not testable has not been terribly good. Witness the fate of psychoanalytic theories of human behavior. Nice try Freud, Jung and all. Their work is still of interest to Literature professors somewhere but in terms of actually understanding and treating mental illness they lost to theories you could test, based on neuroscience or cognitive/behavioral approaches. I think the criticisms of this excessively speculative science is similar. I am thinking of the more exotic forms of string theory or what strikes me as fanciful if not overtly nutty ideas like the multiverse theory. It might be of interest from a philosophical viewpoint perhaps, or as food for thought contributing to some amusing science fiction but whether it will result in anything that objectively extends knowledge describing the particular universe I am interested in, that is the one I inhabit, or offers a possibility of giving rise to technologies that make human life better is another matter. I would not bet much money on this myself, and that really is the ultimate point. Scientists will not get to decide this issue, not if they want to actually be paid to do what they do, that is. Ultimately science needs to be supported financially by tax dollars or private industry and if science can not offer a return on investment to groups like taxpayers, investors and society at large than funding will ( rightfully) dry up and so will the activity. ( That's based on the semi empirical science of economics by the way, which has its limits but at the moment seems more subject to testing than some aspects of physics.) Anyway Try getting a grant from the NIH to study Freudian theories of psychoanalysis. Good luck with that. There will always be folks willing to support non science activities that cater to select tastes, of course. The are those who still fund the opera after all. What will not happen however is that there will be enough funding to pay for lots of physicists or large physics departments. At the end of the day the real questions is not whether this kind of physics is science or speculation or something else. It is whether what you are doing brings value to society such that society wants to pay you for it. That is a testable hypothesis.

I think some of the ambiguity in this discussion is about the meaning of "theory." In common usage, "theory" and "hypothesis" are used interchangeably. But in science, a "theory" is an explanation or model that covers a substantial group of occurrences in nature and has been confirmed (so far) by a substantial number of experiments and observations. Although, rigorously speaking, a theory can not be proved (or confirmed); it is accepted as true because attempts to disprove it have failed and have instead yielded results which are still consistent with the theory. Predictions made by a theory, in this sense, turn out to be verifiable. A hypothesis is a notion that may be supported by logical deduction, but not by verification of the predictions it makes or by attempts to falsify it which end up giving experimental results which turn out to be consistent with the hypothesis. One can posit hypotheses which are unverifiable by experiment. What do you do with unfalsifiable hypotheses? What value do they have?

If it is not testable and/or reproducible, then we have many other categories available. Natural philosophy, metaphysics, pseudo science, religion, and the like come to mind, but you can come up with a new one if it suits your fancy.

Paul Feyerabend makes a similar case as the OP. Science is what scientists do, true enough, and Kuhn was right that "ordinary science" operates within a normalizing paradigm until problem cases arise, provoking a revolution in thinking. Paul's insight, as I understand it, is that the enterprise of science is not organized, stratified, orderly in the way we tend to assume. Lots of different pressures affect the work of people in hard science. Funding, the structures of the academy with tenure and job security - are controlling factors. We have industrial and commercial science. We have ideological science. It matters to fundamental physics what the DoE or CERN will subsidize, and thus it matters what politicians ask the agencies to do.

There is no such thing as "strict" science. Pragmatism (and I know - damn the philosophers!) sorted this out more than a century ago. Darwin! even earlier. If it ain't broke, don't fix it. Cash value!

There are already three camps of scientists:The lowest: Knowledge workers who work in science and technology: The knowledge worker takes what is known/accepted as the truth and applies it to an occupation. The essence of the knowledge worker/non scientist is the unquestioning acceptance of paradox. (By definition we exempt social science workers as an oxymoron as virtually everything in the social sciences is a fabricated construct).

The intermediate: Knowledge worker who takes what is known and innovates something new based on the known science.

The highest is the scientist: The scientist is the person so asks, "how is that the case" when paradox arises and seeks a better understanding. In seeking the better understanding, speculation followed by proof is essential.

The human mind always seeks explanations. The essential difference between the scientist and the science worker is that the science workers explains what is but predicts nothings new; the scientist strives for the deeper understanding and therefore strives to model a better understanding of reality that is not only explanatory but predictive.

"if science is what scientists do, what happens if some scientists stop doing science?"

My solution to this deadlock is for the likes of Tegmark and Witten to stop calling themselves scientists. They are pure mathematicians. I read an interview of Witten. My impression is everything he said is mathematical models that have nothing to do with reality. But to a Platonist, all ideas are real. So if I have the idea of a unicorn, it must be real. I thought we disposed of this nonsense 2,000 years ago? Apparently it is still alive and well among theoretical physicists.

I call this bizarre phenomenon "the revenge of the Platonists" I predict their theories will become ever more bizarre as they divorce themselves from experiments. Who needs cold and hard experiments when fantasy land is easier and much more fun?

Of course scientists must speculate to hypothesize, but they must also support their hypotheses with proof that it agrees with nature. That is truly describing nature. Anything else is speculation, food for thought, cause for further inquiry, but not necessarily true.

I think cosmology is unique scientifically as ideas about the nature of our Universe have led us to the untestable (multiverses and cyclic universes and inflation etc) but that does not mean that theorists should stop theorizing about those aspects of the Universe we would like to know more about, namely singularities/black holes and the reason for or indeed the Universes origin (also classically a singularity).

Relativity has informed us that on the largest scales the Universe can be described quite well and we can indeed run the equations backwards from an expanding to a contracting Universe and where it all begins but relativity fails itself at t=0 and where black holes are concerned too. Add in some quantum mechanics to see if it remedies the situation and we can see that it does not and we are left with gaps in our knowledge and understanding of certain aspects of the Universe.

We need quantum gravity to describe all aspects of the Universe but its not coming easily. Scientists are trying very hard to come to terms with a new theory that doesn't exist as yet and even if it does (string theory) its not predicting much that we can test or much that might be testable.

What one considers to be science is a value judgement, and hence personal and subjective, but for me experiment is the test. The problem with theoretical physics in subjects like particle physics and quantum gravity today is the paucity of relevant new experimental results. Without such, theoretical physics is likely to become just another recondite branch of philosophy, and funded as such.

Jim V. Right, I was thinking of the early Greeks as a historic example of when 'science' was divorced from data.

pete, I'll check out the book, thanks. I think it's right to think about how to get more data. Astronomy is perhaps again the answer, explore more of the EM spectrum and look for anomalies. And of course Ligo is a whole new 'field' to explore.

As an experimentalist I like to quote (paraphrase) Brain Pippard, from the intro to his text "Vibrations". 'I'm not as smart as some, and so I always find it useful to have some data to help guide my thinking.'

I'm with raven lord. The essence of science is reality testing. If the work doesn't care about whether it is consistent with the external world, it's math, or natural philosophy, or even fiction of the Greg Egan sort. But it's important to care. A theory that can't be tested in principle is a clear failure as science. Self-consistency goes without saying, but much of math works fine without any pretence of being realistic, and without any pretence of being science.

As long as you care about reality, the method can be "whatever works", and the description of "what scientists do" is useful. But it can't be dispositive. People who don't have a PhD in an established field or an academic appointment shouldn't be prohibited from being called "scientists".

But then how do you tell who's one and who's not? There are some important "sciences", such as macroeconomics, that are more properly viewed as cargo cult sciences, with all the trappings and ceremonies and high priests, but without the effective core of engagement with the real world.

Your definition seems unsatisfactory to me because of its circularity. It begs the question, which came first, science or the scientist? Adding that "scientists are people who search for useful descriptions of nature" also seems woefully inadequate. Ptolemy provided a useful but completely inaccurate description of nature. Quantum physics is useful but it is hard to argue that it offers a coherent physical description of reality. At root, isn't science the search for an evidence-based understanding of the complex and subtle nature of the physical reality we observe and measure?

Your definition also makes no reference to empiricism which, although currently disfavored by some members of the scientific community, is in fact the only element of science that is fundamentally definitive. Without empiricism science becomes nothing but a secular religion, just a belief system based on mathematical formalisms and some fixed, a priori assumptions about the nature of physical reality.

My own preference for a working definition of science would be along the lines of:

Science is the open-ended investigation into the nature of physical reality using the complimentary probes of empiricism and logic.

Logic in this context would be inclusive of both mathematical and qualitative analysis, as well as perhaps, some philosophy. It might be argued that this definition is not reflective of the way science is actually done in the modern world and there is some truth to that. But then, that is the point. To the extent that modern science no longer considers empiricism central to its methodology, it has become less like the objective science of old and more like a set of fervently held beliefs.

Aren't you, Lee Smolin, Peter Woit and George Ellis all essentially complaining about the same thing, the absence of empirical foundations for too much of modern theoretical physics?

Is learning science? I think that science is a systematic enterprise that builds and organizes knowledge. It can be individual. Learning is science, isn't it - but remembering? Maybe not exactly. With arranging memories and creating new knowledge you definitely do science. Is it good or bad science? - measuring rules.

By evaluating what is acceptable science and what isn't makes the scientific community a religious flock.

"I don't demand that a theory correspond to reality because I don't know what it is. Reality is not a quality you can test with litmus paper. All I'm concerned with is that the theory should predict the results of measurements. "The Nature of Space and Time (1996) by Stephen Hawking and Roger Penrose, p. 121

The question, "What happens if scientists stop doing science?" seems contrary to the assertion, "Science is what scientists do," if the latter is treated as the only viable definition of science. Even the distinction between "good" science (or music) and "bad" science (or "cacophony") implies a stronger definition of science.

Science, like love or morality, is a big concept, a huge configuration space, so it's easy to describe but hard to define, because nearly any definition has so many exceptions. Sabine called it "an emergent concept" -- something that arises from one of our human approaches to existence (again, like love or morality). What was once "Natural Philosophy" has been formalized as "Science."

FWIW, I like Kant's distinction between our Transcendental Idealism and the external Empirical Realism. To me, science is best described as our search to reconcile and explain that (often mysterious) external reality. Which we do both analytically and empirically.

You probably remember Feynman writing home to his wife from a World Conference on Gravity in Poland and despairing ("I am not getting anything out of the meeting. Because there are no experiments this field is not an active one, so few of the best men are doing work in it.") When a field gets starved of data, groupthink and arguments from authority happen. People still have to write papers to get tenured, students need to graduate, etc.

Also, I think the rapid progress in particle physics post WWII was atypical - for military and political reasons there were money for building large accelerators.

When it comes astrophysics, the data can come only from probes and telescopes. It is sad that all this money and effort goes instead to maintaining ISS - and now even into the schemes how to put a man on Mars, and we scientifically will get nothing in return from all this (apart from the medical observation that a year spent in microgravity is not kind to human body).

Here is what Sagan has to say to post empiricists “Who is more humble? The scientist who looks at the universe with an open mind and accepts whatever the universe has to teach us, or somebody who says everything in this book must be considered the literal truth and never mind the fallibility of all the human beings involved?” – Carl Sagan

I am quite skeptical that this issue is relevant for scientists at large.

The rather foolish idea of post-empirical science is being promoted by an unfortunately vocal (and overexposed) part of just a sub-community of physicists. Virtually all of the remaining scientists (including the overwhelming majority of physicists) go on quietly with their research, implicitly or explicitly following the modern scientific method which includes empirical verification as an essential ingredient.I doubt anyone can seriously consider post-empirical science claim outside this small community.

This of course does not imply at all that it is not worth investigating the deep mathematical structure of more or less established theories and/or pondering on issues such as quantum gravity even in the lack of realistic hopes of empirical validation. It just means that for a scientific theory to become well established it should have passed a good number of empirical tests. Possibly and preferably including some new phenomena predicted by the theory and not previously put forward by other frameworks.

Well established theories in physics are, for instance, special and general relativity, statistical mechanics, quantum mechanics, classical mechanics (in its realm of applicability), electroweak theory, etc… This are amongst the undisputed fundamentals we teach our students and what we should try to percolate towards the general public.If you do not get to this point of empirical validation, your theory will never considered as well established. No matter how smart you are, how elegant is your theory or how difficult is the task you set yourself at. Bad luck if you chose the wrong horse, it happens to the best people too.Look for instance at the Glashow and Georgi GUT killed by the lack of convincing evidence of proton decay.Or look at quantum information, EPR, Bell inequalities, etc. One have to recognise that the field took really off when experiments started to complement the excellent early work of the theorists.

It is also telling to see how many of the same people who now are advocating post-empirical science are the same that for the last 20 years or so have been claiming triumphally that some empirical verification of SUSY and/or other string theory vaguely related phenomena would have been found at LHC. Now that these hopes are vanishing, they suddenly try to change the rules of modern science to do without empirical validation.

"Well established theories in physics are, for instance, special and general relativity, statistical mechanics, quantum mechanics, classical mechanics (in its realm of applicability), electroweak theory, etc… This are amongst the undisputed fundamentals we teach our students and what we should try to percolate towards the general public."

If these fundamentals were correct, hints like this one would not exist:

Peter Woit: "If, as seems increasingly all too possible, we're now at an endpoint of fundamental physics..." http://www.math.columbia.edu/~woit/wordpress/?p=9444

It is time to start suspecting that the root of the evil is in the fundamentals, not in today's post-empiricism. The following quotations suggest that Einstein's constant-speed-of-light postulate, if false, has killed physics:

"The speaker Joao Magueijo, is a Reader in Theoretical Physics at Imperial College, London and author of Faster Than the Speed of Light: The Story of a Scientific Speculation. He opened by explaining how Einstein's theory of relativity is the foundation of every other theory in modern physics and that the assumption that the speed of light is constant is the foundation of that theory. Thus a constant speed of light is embedded in all of modern physics and to propose a varying speed of light (VSL) is worse than swearing! It is like proposing a language without vowels." http://www.thegreatdebate.org.uk/VSLRevPrnt.html

"...Dr. Magueijo said. "We need to drop a postulate, perhaps the constancy of the speed of light." http://www.nytimes.com/2002/12/31/science/e-and-mc2-equality-it-seems-is-relative.html

"But the researchers said they spent a lot of time working on a theory that wouldn't destabilise our understanding of physics. "The whole of physics is predicated on the constancy of the speed of light," Joao Magueijo told Motherboard. "So we had to find ways to change the speed of light without wrecking the whole thing too much." http://www.telegraph.co.uk/technology/2016/12/06/speed-light-discovered/

Joao Magueijo, Faster Than the Speed of Light, p. 250: "Lee [Smolin] and I discussed these paradoxes at great length for many months, starting in January 2001. We would meet in cafés in South Kensington or Holland Park to mull over the problem. THE ROOT OF ALL THE EVIL WAS CLEARLY SPECIAL RELATIVITY. All these paradoxes resulted from well known effects such as length contraction, time dilation, or E=mc^2, all basic predictions of special relativity. And all denied the possibility of establishing a well-defined border, common to all observers, capable of containing new quantum gravitational effects." http://www.amazon.com/Faster-Than-Speed-Light-Speculation/dp/0738205257

Aristotle wouldn't have done better with "more and better data." He wrote that women have 80 teeth and took their red menstrual blood as evidence that they do not have souls. (I mean, it's true that they don't, neither do men, but he was going about this in a very wrong way.) Aristotle was an idiot.

Unknown: do you have a source for your claims on Aristotle? Containing actual quotes from Aristotle's books? I have read a couple of articles on Aristotle and one book about Ancient Greece and have never heard of them previously.

On the matter of woman's teeth this seems like a good reference to me:

Since this natural variation is so well-known to anthropologists, I was intrigued to find in a comment to a post at Gene Expression that Aristotle believed men had more teeth than women. I went in search of the essential citation, and found it in "The History of Animals," book 2, part 1 (translated by D'Arcy Wentworth Thompson):

"Males have more teeth than females in the case of men, sheep, goats, and swine; in the case of other animals observations have not yet been made ..."

There may be no accounting for Aristotle's claim that men have more teeth than women, since on average they are the same. On the other hand, with the variation in third molar eruption [wisdom teeth--JV] it is quite possible that the women available for Aristotle to examine might have -- by chance -- had fewer teeth. [end quote]

I have also seen the speculation that Greek women in Aristotle's time did not have sufficient calcium in their diet to make up for birthing children and therefore were more prone to losing teeth than men. In any case it seems that Aristotle did make observations and base his conclusions on them, but that the data was often biased or insufficient.

"For the female is, as it were, a mutilated male, and the menstrual fluids are semen, only not pure; for there is only one thing they have not in them, the principle of soul." is from On the Generation of Animals. I think the teeth bit was in de Partibus, but I haven't written that one down.

The proposition from one side of science saying that another side of science is not doing "real" science is counterproductive. This is politicizing science.

Science is all about interpretation of measurements and if one scientist disagrees with an interpretation, then they should say so. If a scientist disagrees with a measurement, then they should say so.

Scientific civil wars over the definition of a word like naturalism seem rather trivial from the outside looking in. What in the world is the meaning of meaning?

Can't science focus on the observables and measurements that objective observers can agree with? Why do these arguments seem to amount to large heaps of complex math that really have little meaning to any but a few and only serve to prolong the discourse, not resolve it?

"...Einstein's theory of relativity is the foundation of every other theory in modern physics and that the assumption that the speed of light is constant is the foundation of that theory. Thus a constant speed of light is embedded in all of modern physics and to propose a varying speed of light (VSL) is worse than swearing!"

The first sentence of this quote mischaracterizes Einstein's theory. In relativity theory the speed of light is constant only in a vacuum, in an inertial reference frame. That is, the constancy law only applies under Special Relativity conditions. Special Relativity provides an ideal theoretical baseline that is only approximated in reality. In non-inertial reference frames the speed of light varies with position. Einstein himself was very clear on this point:

"...according to the general theory of relativity, the law of the constancy of light in vacuo...cannot claim any unlimited validity. A curvature of rays of light can only take place when the velocity of propagation of light varies with position.-Albert Einstein, Relativity, The Special and General Theory

This predicted inconstancy of light speed has been observed (Shapiro delay). The problems identified in the second sentence you quoted are real enough, but they are not a consequence of relativity theory. They are a direct result of the failure by theorists to factor in a variable speed of light for non-inertial frames when constructing their GR based models.

Peter Woit runs a blog called "Not Even Wrong" (not to mention his book), and he is obviously (and rightly so) worried about the lack of new high energy experimental inputs (not to mention the unhealthy dominance of a not-even-wrong framework over high energy theoretical physics). I am quite surprised to see that you are able to misinterpret him so much.

The rest of your comment nicely underlines the pitfalls of post-empirical thinking: Special relativity -- as you correctly noted -- lies at the very core of modern physics, and therefore over the last century has gathered an unparalleled number of empirical confirmations, both direct and indirect. This is why, for instance, every sane physicist was 99.9% sure superluminal neutrinos were due to an experimental error and was flabbergasted by how badly OPERA handled the issue. Special Relativity is obviously here to stay unless enough convincing empirical falsifications can be gathered against it. Too bad if it is in the way of your pet theory of everything.

I am not at all an expert of VSL theories, but note that even Joao Magueijo -- for how much of an irritating full of himself self-promoting maverick he can be -- correctly recognise that for his theory to be successful i) it should not contradict well established empirical results and ii) it should pass some novel empirical test.To me, the fact that it took them almost 20 years to at least formulate an in principle observable test for VCL clearly does not bode well, but well, who knows...

Thank you for ["For the female is, as it were, a mutilated male, and the menstrual fluids are semen, only not pure; for there is only one thing they have not in them, the principle of soul." is from On the Generation of Animals.] but I do not read it the way you do.

For me it says that semen contains active seeds of life, menstrual fluids do not - which is a statement of fact. (Semen can be and is used for artificial insemination; menstrual fluids can not. Perhaps the Greeks had tried this - I don't know.) Probably it was written in the Greek idioms of the time, which may not translate well. The "mutilated male" hypothesis was, I grant you, another speculation based on not enough good data.

It seems clear to me from the link I cited and its quotes from Aristotle that he had counted some people's teeth and would not say that women had 80 teeth, although again there is always the chance of a translation error.

Speculation is to human thought as mutation is to biological evolution. Both proceed by trial and error, which requires a source of trials, and most speculations and mutations turn out to be bad. (Almost getting back on topic here:). It is the lack of good selection criteria which is the problem, not speculation itself.

So how would you classify this: https://www.youtube.com/watch?v=LYMqc1zzJnU

It sounds like cacophony to me, but it calls itself music and 341 people said they liked it while only 31 said they did not. There are many different kinds of music that sound like noise; people make albums of it and people buy these albums. I'm not sure where you draw the line between music and cacophony. I would call it music if people do music-like things with it: play it on purpose, record it, buy it, listen to it on purpose, etc.

To me the interesting part starts not when we classify something as "science" or "not science" in a binary manner, but when we start trying to figure out what counts as good science. What are our criteria, or rules of thumb? I've got mine, but this comment is probably not the place to go into them.

No need to get philosophical or tautological here. Science is the business of building models of the world. Ergo, string theorists are scientists. But there is an addendum: some models are more useful than others. QED is fantastically useful. String theory not so much. My model of the invisible magic pixie who hides my car keys not at all.

"I will not approve any more comments on what you believe is wrong with special relativity, it's off-topic."

OK, but the hypothesis that today's problems may have originated in the past deserves some attention, doesn't it? "Physics is dead" has already entered popular culture and soon calamities may occur, in terms of funding:

Leonard: "I know I said physics is dead, but it is the opposite of dead. If anything, it is undead, like a zombie." https://www.youtube.com/watch?v=GDNP9KOEdh0

I literally just wrote a book about the problems with the foundations of physics today. Isn't that enough evidence I pay attention? Trust me when I say that the speed of light has nothing to do with it.

In case your comment was addressed to me, no that's not what I'm saying. Not sure how you got there. I am not particularly known for mincing words, so trust me when I say if that's what I had wanted to say, I'd have said it.

On somewhat related note: epistemology fascinates me though. Why SMART people believe (do?) stupid things. Many times bad actions stem from bad beliefs (I have had 100 beliefs rotated during my life time). Some of them come from learning.

Tyler Cowen did one amazing talk on stories. Here's one great link:https://youtu.be/RoEEDKwzNBw?t=427

"Be more comfortable with agnostic, and I mean this about the things that make you feel good. It's so easy to pick a few areas you're agnostic in, and then feel good about like, "I'm agnostic about religion, or politics." It's a kind of portfolio move you make to be more dogmatic elsewhere, right? Sometimes, the most intellectually trustworthy people are the ones who pick one area, and they're totally dogmatic in that. So pig-headedly unreasonable you think, "How can they possibly believe that!?" But it soaks up their stubbornness, and then on other things, they can be pretty open-minded. "

My guess there are two reasons:1. Evolutionary reasons: evolution never made us to understand the world but to win resources. All of us engage in signalling games. The physicists are not exempt. Usually any human transaction means loss of status on some end.2. Pychological reasons: the more. The more you advertise a belief, the more your identity is wrapped around, the less likely you are to reverse it. I know from experience. This is also probably adaptive behaviour.

"Can't science focus on the observables and measurements that objective observers can agree with? Why do these arguments seem to amount to large heaps of complex math that really have little meaning to any but a few and only serve to prolong the discourse, not resolve it?"

I think that the concept of an objective observer is an oxymoron. I pointed this out not just to make a pun, but i think its hinting a deep conceptual problems of the "timeless mathematical truth" strategies that alot of the critized approaches this blog entry was referring to adopt.

What rational justification do we REALLY have for expecting objective expectations? One argument is consistency, as otherwise two observers will be in disagreement. But so what? Who said this a real inconsistency? Objectivity is NICE and simplifies matters, but thinking of it as a constraint may fallaciously lead us wrong from the point of view of trying to understand nature (ie finding theories that actually reflect how nature works). This relates also as you see to symmetry princiuples in physics, like are they REALLY mathematical constraints in nature? or are they rather EMERGENT? the situation at a steady state is the same but the causal mechanism is very different.

This is why i think its dangerous for some research programs that decouples and diverge in the world of applied mathematics. Its not physics as in a "natural science" anymore. Thats not to say applied mathematics isnt great.

"But if you can't trust physicists, how do you know you can trust any other scientists?"

That's simple. You should know that you cannot trust other scientists too. One cannot trust people who work from one grant to next grant and have to care about getting the next grant. Would you trust judges with such employment conditions? Why would you trust scientists?

Of course, even under such horrible conditions scientists deserve more trust than journalists. But this is not really a compliment, it is more like saying this woman deserves more trust than a prostitute. If you want science, make science possible, giving scientists adequate working conditions. And for a theoretician, who does not need that much more than a laptop to write his articles, adequate working condition simply means a safe income, forever. Tenure from day one after PhD, even after Master. It should not be a good paid job, not at all, this is not what scientists care about, but safety is what matters, what makes them indepedent scientists.

I think it was Duchamp that quipped that Art is what artists do. It looks like scientists have caught up! Surely both sides are necessary for a healthy community - conservatives and progressives; it results in a healthy tension so long as it does not descend into an unhealthy bickering. Also, surely it needs to be pointed out that when the last revolution was kicked off it was by experiment (blackbody radiation), and we're really nowhere near close enough to start probing Planck level physics in a direct way. It might be the case that this situation of higher and ever higher tower of higher speculations will go on for the forseeable future - well, until physicists have a hangover. Maybe they're having one now?

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